Probit Model
Also known as · probit · probit regression
The probit model is a binary-outcome model that estimates , where is the standard-normal CDF. By squashing the linear prediction into , probit cures the LPM's out-of-range-probability problem; the price is non-linearity in parameters, so the model is estimated by MLE rather than OLS.
When to use
Use probit when the LPM's unbounded predictions or constant marginal effects are uncomfortable — typically when many fitted values approach 0 or 1, or when the substantive question is about probabilities at the extremes. In practice probit and logit give nearly identical predictions; the choice rarely matters. Raw coefficients tell you the direction only; for the probability change you need the marginal effect (see the Computing marginal effects (logit / probit) recipe). Hypothesis testing uses the Likelihood Ratio Test rather than the F-test.